Local upregulation of interleukin-1 beta in aortic dissecting aneurysm: correlation with matrix metalloproteinase-2, 9 expression and biomechanical decrease

Elastin-specific MR probe for visualization and evaluation of an interleukin-1β targeted therapy for atherosclerosis

Atherosclerosis is a chronic inflammatory condition of the arteries and represents the primary cause of various cardiovascular diseases. Despite ongoing progress, finding effective anti-inflammatory therapeutic strategies for atherosclerosis remains a challenge. Here, we assessed the potential of molecular magnetic resonance imaging (MRI) to visualize the effects of 01BSUR, an anti-interleukin-1β monoclonal antibody, for treating atherosclerosis in a murine model. Male apolipoprotein E-deficient mice were divided into a therapy group (01BSUR, 2 × 0.3 mg/kg subcutaneously, n = 10) and control group (no treatment, n = 10) and received a high-fat diet for eight weeks. The plaque burden was assessed using an elastin-targeted gadolinium-based contrast probe (0.2 mmol/kg intravenously) on a 3 T MRI scanner. T1-weighted imaging showed a significantly lower contrast-to-noise (CNR) ratio in the 01BSUR group (pre: 3.93042664; post: 8.4007067) compared to the control group (pre: 3.70679168; post: 13.2982156) following administration of the elastin-specific MRI probe (p < 0.05). Histological examinations demonstrated a significant reduction in plaque size (p < 0.05) and a significant decrease in plaque elastin content (p < 0.05) in the treatment group compared to control animals. This study demonstrated that 01BSUR hinders the progression of atherosclerosis in a mouse model. Using an elastin-targeted MRI probe, we could quantify these therapeutic effects in MRI.

Matrix metalloproteinases in aortic dissection

Aortic dissection, characterized by a high immediate mortality, is primarily caused by excessive bleeding within the walls of the aorta or a severe tear within the intimal layer of the aorta. Inflammation, as well as oxidative stress and the degradation of extracellular matrix (ECM), are significant factors in the development and occurrence of aortic dissection. Matrix metalloproteinases (MMPs) are pivotal enzymes responsible for degrading the ECM. Inflammatory factors and oxidants can interact with MMPs, indicating the potential significance of MMPs in aortic dissection. A substantial body of evidence indicates that numerous MMPs are significantly upregulated in aortic dissection, playing a critical role in ECM degradation and the pathogenesis of aortic dissection. Furthermore, targeting these enzymes has demonstrated potential in facilitating ECM restoration and reducing the incidence of aortic dissection. This review initially provides a brief overview of MMP biology before delving into their expression patterns, regulatory mechanisms, and therapeutic applications in aortic dissection. A profound comprehension of the catabolic pathways associated with aortic dissection is imperative for the future development of potential preventive or therapeutic bio-interventions for aortic dissection.

Tea polyphenol nanoparticles enable targeted siRNA delivery and multi-bioactive therapy for abdominal aortic aneurysms

Abdominal aortic aneurysm (AAA) is a life-threatening vascular disease, while there is a lack of pharmaceutical interventions to halt AAA progression presently. To address the multifaceted pathology of AAA, this work develops a novel multifunctional gene delivery system to simultaneously deliver two siRNAs targeting MMP-2 and MMP-9. The system (TPNs-siRNA), formed through the oxidative polymerization and self-assembly of epigallocatechin gallate (EGCG), efficiently encapsulates siRNAs during self-assembly. TPNs-siRNA safeguards siRNAs from biological degradation, facilitates intracellular siRNA transfection, promotes lysosomal escape, and releases siRNAs to silence MMP-2 and MMP-9. Additionally, TPNs, serving as a multi-bioactive material, mitigates oxidative stress and inflammation, fosters M1-to-M2 repolarization of macrophages, and inhibits cell calcification and apoptosis. In experiments with AAA mice, TPNs-siRNA accumulated and persisted in aneurysmal tissue after intravenous delivery, demonstrating that TPNs-siRNA can be significantly distributed in macrophages and VSMCs relevant to AAA pathogenesis. Leveraging the carrier's intrinsic multi-bioactive properties, the targeted siRNA delivery by TPNs exhibits a synergistic effect for enhanced AAA therapy. Furthermore, TPNs-siRNA is gradually metabolized and excreted from the body, resulting in excellent biocompatibility. Consequently, TPNs emerges as a promising multi-bioactive nanotherapy and a targeted delivery nanocarrier for effective AAA therapy.

The mechanism and therapy of aortic aneurysms

Aortic aneurysm is a chronic aortic disease affected by many factors. Although it is generally asymptomatic, it poses a significant threat to human life due to a high risk of rupture. Because of its strong concealment, it is difficult to diagnose the disease in the early stage. At present, there are no effective drugs for the treatment of aneurysms. Surgical intervention and endovascular treatment are the only therapies. Although current studies have discovered that inflammatory responses as well as the production and activation of various proteases promote aortic aneurysm, the specific mechanisms remain unclear. Researchers are further exploring the pathogenesis of aneurysms to find new targets for diagnosis and treatment. To better understand aortic aneurysm, this review elaborates on the discovery history of aortic aneurysm, main classification and clinical manifestations, related molecular mechanisms, clinical cohort studies and animal models, with the ultimate goal of providing insights into the treatment of this devastating disease. The underlying problem with aneurysm disease is weakening of the aortic wall, leading to progressive dilation. If not treated in time, the aortic aneurysm eventually ruptures. An aortic aneurysm is a local enlargement of an artery caused by a weakening of the aortic wall. The disease is usually asymptomatic but leads to high mortality due to the risk of artery rupture.

Preoperative systemic inflammatory response index predicts long-term outcomes in type B aortic dissection after endovascular repair

Objectives

Inflammation is a hallmark of the initial development and progression of aortic dissection. This study aimed to investigate the value of preoperative inflammatory biomarkers in predicting aorta-related adverse events (AAEs) after thoracic endovascular aortic repair (TEVAR) for type B aortic dissection.

Methods

We included all patients who underwent TEVAR for type B aortic dissection between November 2016 and November 2020 in this single-center, retrospective cohort study. Patients were divided into two groups: the AAEs group (n = 75) and the non-AAEs group (n = 126). Preoperative inflammatory biomarkers were recorded, including neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), platelet-to-lymphocyte ratio (PLR), systemic immune inflammation index (SII), and systemic inflammatory response index (SIRI). Patients were followed-up for the development of AAEs. Prediction accuracy of inflammatory biomarkers for AAEs were evaluated using the area under the receiver operating characteristic curves.

Results

This study included 201 patients, of whom 80.0% were men, with a mean age of 59.1 ± 12.5 years. A total of 75 patients developed AAEs after TEVAR. The AUCs of NLR, MLR, PLR, SII, and SIRI for AAEs were.746,.782,.534,.625 and.807, respectively. Age and SIRI were independent risk factors for the AAEs after TEVAR (HR 3.264, p <.001; HR 4.281, p <.001, respectively). Survival analysis revealed significantly lower AAE-free status in patients with preoperative SIRI > = 4 (p <.001).

Conclusion

Increased preoperative SIRI and age are independent risk factors for AAEs after TEVAR in type B aortic dissection.

Cytokines in Abdominal Aortic Aneurysm: Master Regulators With Clinical Application

Abdominal aortic aneurysm (AAA) is a potentially life-threatening disorder with a mostly asymptomatic course where the abdominal aorta is weakened and bulged. Cytokines play especially important roles (both positive and negative) among the molecular actors of AAA development. All the inflammatory cascades, extracellular matrix degradation and vascular smooth muscle cell apoptosis are driven by cytokines. Previous studies emphasize an altered expression and a changed epigenetic regulation of key cytokines in AAA tissue samples. Such cytokines as IL-6, IL-10, IL-12, IL-17, IL-33, IL-1β, TGF-β, TNF-α, IFN-γ, and CXCL10 seem to be crucial in AAA pathogenesis. Some data obtained in animal studies show a protective function of IL-10, IL-33, and canonical TGF-β signaling, as well as a dual role of IL-4, IFN-γ and CXCL10, while TNF-α, IL-1β, IL-6, IL-12/IL-23, IL-17, CCR2, CXCR2, CXCR4 and the TGF-β noncanonical pathway are believed to aggravate the disease. Altogether data highlight significance of cytokines as informative markers and predictors of AAA. Pathologic serum/plasma concentrations of IL-1β, IL-2, IL-6, TNF-α, IL-10, IL-8, IL-17, IFN-γ, and PDGF have been already found in AAA patients. Some of the changes correlate with the size of aneurysms. Moreover, the risk of AAA is associated with polymorphic variants of genes encoding cytokines and their receptors: CCR2 (rs1799864), CCR5 (Delta-32), IL6 (rs1800796 and rs1800795), IL6R (rs12133641), IL10 (rs1800896), TGFB1 (rs1800469), TGFBR1 (rs1626340), TGFBR2 (rs1036095, rs4522809, rs1078985), and TNFA (rs1800629). Finally, 5 single-nucleotide polymorphisms in gene coding latent TGF-β-binding protein (LTBP4) and an allelic variant of TGFB3 are related to a significantly slower AAA annual growth rate.

Integrated analysis and the identification of a circRNA-miRNA-mRNA network in the progression of abdominal aortic aneurysm

Background

Abdominal aortic aneurysm (AAA) is a disease commonly seen in the elderly. The aneurysm diameter increases yearly, and the larger the AAA the higher the risk of rupture, increasing the risk of death. However, there are no current effective interventions in the early stages of AAA.

Methods

Four gene expression profiling datasets, including 23 normal artery (NOR) tissue samples and 97 AAA tissue samples, were integrated in order to explore potential molecular biological targets for early intervention. After preprocessing, differentially expressed genes (DEGs) between AAA and NOR were identified using LIMMA package. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis were conducted using the DAVID database. The protein-protein interaction network was constructed and hub genes were identified using the STRING database and plugins in Cytoscape. A circular RNA (circRNA) profile of four NOR tissues versus four AAA tissues was then reanalyzed. A circRNA-miRNA-mRNA interaction network was constructed after predictions were made using the Targetscan and Circinteractome databases.

Results

A total of 440 DEGs (263 up-regulated and 177 down-regulated) were identified in the AAA group, compared with the NOR group. The majority were associated with the extracellular matrix, tumor necrosis factor-α, and transforming growth factor-β. Ten hub gene-encoded proteins (namely IL6, RPS27A, JUN, UBC, UBA52, FOS, IL1B, MMP9, SPP1 and CCL2) coupled with a higher degree of connectivity hub were identified after protein‐protein interaction network analysis. Our results, in combination with the results of previous studies revealed that miR-635, miR-527, miR-520h, miR-938 and miR-518a-5p may be affected by circ_0005073 and impact the expression of hub genes such as CCL2, SPP1 and UBA52. The miR-1206 may also be affected by circ_0090069 and impact RPS27A expression.

Conclusions

This circRNA-miRNA-mRNA network may perform critical roles in AAA and may be a novel target for early intervention.

Establishment and effect evaluation of an aortic dissection model induced by different doses of β-aminopropionitrile in rats

INTRODUCTION

Given the controversy regarding the appropriate dose of β-aminopropionitrile for induction of aortic dissection models in rats, the purpose of this study was to explore the most suitable concentration of β-aminopropionitrile to establish a high-incidence and low-mortality aortic dissection model.

METHODS

Eighty three-week-old male Sprague-Dawley rats were equally divided into four groups: a control group, a 0.06% β-aminopropionitrile group, a 0.08% β-aminopropionitrile group and a 0.1% β-aminopropionitrile group. Initial experiments were performed on the control group, which was not treated with β-aminopropionitrile (and drank water freely), and the other three groups, which were given different concentrations of β-aminopropionitrile solution daily (0.06%, 0.08% and 0.1%). Subsequently, on the 40th day, osmotic minipumps administering 1 μg/kg per min angiotensin II (Ang II) were implanted subcutaneously into the β-aminopropionitrile groups, while the control group was continuously pumped with normal saline. The rats were euthanized 48 h after implantation. All rats that died before the expected end time of the experiment were autopsied immediately, and the aortas were dissected. The rats surviving at the end of the experiment were sacrificed by an overdose of sodium pentobarbital, and tissue samples were harvested for further analyses.

RESULTS

The mean survival days were significantly different among the groups, with 39.1 ± 6.04 days in the 0.08% β-aminopropionitrile group and 32.7 ± 9.85 days in the 0.1% β-aminopropionitrile group (P = 0.0178) at the end of the experiment. Compared with those in the 0.06% β-aminopropionitrile group, the rates of aortic dissection were significantly higher in the 0.08% β-aminopropionitrile group and the 0.1% β-aminopropionitrile group (P = 0.0015 and P = 0.0005, respectively), while there was no significant difference between the 0.08% β-aminopropionitrile group and the 0.1% β-aminopropionitrile group (P = 0.723) at 70% and 75%, respectively. However, the rupture rates were significantly different between the 0.08% β-aminopropionitrile group and the 0.1% β-aminopropionitrile group (55% versus 20%, P = 0.022). Hematoxylin-eosin staining of the aortic tissue sections of the β-aminopropionitrile group showed that red blood cells entered the pseudocavity in the vascular wall, while the vascular wall structure of the control group was intact. Compared with control rats, which were intact and free from fracture, β-aminopropionitrile-treated rats had fewer collagen fibers and exhibited fracture. Magnetic resonance imaging showed that the aortic intimae of the aortic dissection rats showed double lumens and intimal tears.

CONCLUSIONS

An aortic dissection model with a high incidence and low mortality was successfully and stably developed with 0.08% β-aminopropionitrile. This model will enable further studies investigating aortic dissection pathogenesis and drug therapy. Magnetic resonance imaging may be a reliable technique for imaging the aorta in rats.

Updates in aortic wall pathology

Several studies have investigated the pathogenesis of aortic wall abnormalities such as aortic dissection or aneurysm; however, the comprehensive pathological in situ event involved in the development of the disease is not understood well. The vasa vasorum form a network of capillaries or venules around the adventitia and outer media, which play an important role in the aortic wall structure and function. Impairment of their function may induce tissue hypoxia, impede the transfer of cellular nutrients, and cause aortic medial degeneration, which is considered the major predisposing factor to this aortic wall pathology. This review updates our understanding of the pathological changes in the aortic media and vasa vasorum of patients with aortic dissection and aortic aneurysm.

Expression and role of lumican in acute aortic dissection: A human and mouse study

Introduction

Aortic dissection (AD) is a life-threatening emergency, and lumican (LUM) is a potential Biomarker for AD diagnosis. We investigated LUM expression patterns in patients with AD and explored the molecular functions of Lum in AD mice model.

Methods

LUM expression patterns were analyzed using aortic tissues of AD patients, and serum soluble LUM (s-LUM) levels were compared between patients with acute AD (AAD) and chronic AD (CAD). Lum-knockout (Lum^−/−) mice were challenged with β-aminopropionitrile (BAPN) and angiotensin II (Ang II) to induce AD. The survival rate, AD incidence, and aortic aneurysm (AA) in these mice were compared with those in BAPN–Ang II–challenged wildtype (WT) mice. Tgf-β/Smad2, Mmps, Lum, and Nox expression patterns were examined.

Results

LUM expression was detected in the intima and media of the ascending aorta in patients with AAD. Serum s-LUM levels were significantly higher in patients with AAD than CAD. Furthermore, AD-associated mortality and thoracic aortic rupture incidence were significantly higher in the Lum^−/− AD mice than in the WT AD mice. However, no significant pathologic changes in AA were observed in the Lum^−/− AD mice compared with the WT AD mice. The BAPN–Ang II–challenged WT and Lum^−/− AD mice had higher Tgf-β, p-Smad2, Mmp2, Mmp9, and Nox4 levels than those of non-AD mice. We also found that Lum expression was significantly higher in the BAPN-Ang II–challenged WT in comparison to the unchallenged WT mice.

Conclusion

LUM expression was altered in patients with AD display increased s-LUM in blood, and Lum^−/− mice exhibited augmented AD pathogenesis. These findings support the notion that LUM is a biomarker signifying the pathogenesis of injured aorta seen in AAD. The presence of LUM is essential for maintenance of connective tissue integrity. Future studies should elucidate the mechanisms underlying LUM association in aortic changes.

Transplantation of bone marrow-derived mesenchymal stem cells with silencing of microRNA-138 relieves pelvic organ prolapse through the FBLN5/IL-1β/elastin pathway

Nondegradable transvaginal polypropylene meshes for treating pelvic organ prolapse (POP) are now generally unavailable or banned due to serious adverse events. New tissue engineering approaches combine degradable scaffolds with mesenchymal stem/stromal cells from human endometrium (eMSC). In this study, we investigate effect of microRNA-138 (miR-138) regulation on bone marrow-derived mesenchymal stem cells (BMSCs) and the efficacy of BMSC transplantation therapy in a rat POP model. We first identified FBLN5 as a target of miR-138. miR-138, fibulin-5 (FBLN5), interleukin-1β (IL-1β), and elastin expression in uterosacral ligament of POP patients and controls were detected by reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blot analysis. After isolation and identification, BMSCs were treated to alter their expression of miR-138 or FBLN5. Proliferation of BMSCs was analyzed by CCK-8. After establishing the rat pelvic floor dysfunction (PFD) model, we evaluated efficacy of BMSC injection by applying leak point pressure (LPP) and the conscious cystometry (CMG) tests. miR-138 inhibition resulted in increased viability of BMSCs and elevated their secretion of elastin, while downregulating IL-1β expression. BMSCs with inhibited miR-138 improved LPP and conscious CMG results in vivo. Taken together, miR-138 could be a potential therapeutic target for treating POP in conjunction with tissue engineering.

The Role of Inflammation and Myeloperoxidase-Related Oxidative Stress in the Pathogenesis of Genetically Triggered Thoracic Aortic Aneurysms

Genetically triggered thoracic aortic aneurysms (TAAs) are usually considered to exhibit minimal levels of inflammation. However, emerging data demonstrate that specific features of an inflammatory response can be observed in TAA, and that the extent of the inflammatory response can be correlated with the severity, in both mouse models and in human studies. Myeloperoxidase (MPO) is a key mediator of the inflammatory response, via production of specific oxidative species, e.g., the hypohalous acids. Specific tissue modifications, mediated by hypohalous acids, have been documented in multiple cardiovascular pathologies, including atherosclerosis associated with coronary artery disease, abdominal aortic, and cerebral aneurysms. Similarly, data are now emerging that show the capacity of MPO-derived oxidative species to regulate mechanisms important in TAA pathogenesis, including alterations in extracellular matrix homeostasis, activation of matrix metalloproteinases, induction of endothelial dysfunction and vascular smooth muscle cell phenotypic switching, and activation of ERK1/2 signaling. The weight of evidence supports a role for inflammation in exacerbating the severity of TAA progression, expanding our understanding of the pathogenesis of TAA, identifying potential biomarkers for early detection of TAA, monitoring severity and progression, and for defining potential novel therapeutic targets.

Blocking Interleukin-1 Beta Reduces the Evolution of Thoracic Aortic Dissection in a Rodent Model

OBJECTIVE

Thoracic aortic dissection (TAD) is associated with matrix changes, biochemical changes, and inflammatory markers like interleukin-1 beta (IL-1β). However, the exact mechanism remains unknown. This study aimed to investigate the role of IL-1β, matrix metalloproteinase (MMP)-2, MMP-9, smooth muscle cell apoptosis, and elastic fibre fracture in the development of TAD in a rat model.

METHODS

The TAD rat model was induced by β-aminopropionitrile (BAPN). TAD was investigated in 112 male Sprague-Dawley rats, which were equally divided into four groups of 28 rats (Control, BAPN, BAPN + IL-1β, and BAPN + IL-1β antibody). Systolic blood pressure, survival, and the development of TAD were measured after six weeks. Expression of IL-1β, MMP-2, and MMP-9 was measured by Western blot. Apoptosis, aortic elastin concentration, and biomechanical characteristics were measured by the TdT mediated dUTP nick end labelling assay, Victoria blue staining, and in vitro testing.

RESULTS

During six weeks, the mortality was 0% (0/28) in the control group, 53.6% (15/28) in the BAPN group (p < .001 compared with the control group), 75.0% (21/28) in the BAPN + IL-1β group (p = .007 compared with the BAPN group), and 35.7% (10/28) in the BAPN + IL-1β antibody group (p = .023 compared with BAPN group and p < .001 compared with the BAPN + IL-1β group). IL-1β treatment deteriorates BAPN induced mortality and aneurysm expansion, which were attenuated by anti-IL-1β treatment. In BAPN + IL-1β group, stress and strain parameters were decreased by 13.5%-53.5% and elastin content was decreased by 14%, and IL-1β, MMP-2, and MMP-9 were expressed higher by 117%, 108%, and 75% when compared with the rats in the BAPN group. Contrarily, in the BAPN + IL-1β antibody group, the above changes could be completely (strain, elastin content, and expression of MMP-2) or partly (elasticity modulus, stress, and expression of MMP-9) blocked by anti-IL-1β treatment.

CONCLUSION

IL-1β plays a critical role in TAD formation by altering the expression of MMP-2 and MMP-9, degrading the aortic wall matrix, causing elastic fibre rupture, and changing the stress or strain of the aortic wall. Anti-IL-1β reduces the later effects and could be one of the molecular targets for prognosis and drug treatment of TAD in the future.

Inflammation in thoracic aortic aneurysms

Mutations in extracellular matrix and smooth muscle cell contractile proteins predispose to thoracic aortic aneurysms in Marfan syndrome (MFS) and related disorders. These genetic alterations lead to a compromised extracellular matrix-smooth muscle cell contractile unit. The abnormal aortic tissue responds with defective mechanosensing under hemodynamic stress. Aberrant mechanosensing is associated with transforming growth factor-beta (TGF-β) hyperactivity, enhanced angiotensin-II (Ang-II) signaling, and perturbation of other cellular signaling pathways. The downstream consequences include enhanced proteolytic activity, expression of inflammatory cytokines and chemokines, infiltration of inflammatory cells in the aortic wall, vascular smooth muscle cell apoptosis, and medial degeneration. Mouse models highlight aortic inflammation as a contributing factor in the development of aortic aneurysms. Anti-inflammatory drugs and antioxidants can reduce aortic oxidative stress that prevents aggravation of aortic disease in MFS mice. Targeting TGF-β and Ang-II downstream signaling pathways such as ERK1/2, mTOR, PI3/Akt, P38/MAPK, and Rho kinase signaling attenuates disease pathogenesis. Aortic extracellular matrix degradation and medial degeneration were reduced upon inhibition of inflammatory cytokines and matrix metalloproteinases, but the latter lack specificity. Treating inflammation associated with aortic aneurysms in MFS and related disorders could prove to be beneficial in limiting disease pathogenesis.